Paper-making machines



Sept. 25, 1956 su s 2,764,068

PAPER-MAKING MACHINES Filed NOV. 24, 1954 3 Sheets-Sheet l In ven lor75M Sun/sea r Sept. 25, 1956 'r. suTHERsf 2,764,068

PAPER-MAKING MACHINES Filed Nov. 24, 1954 :s Shets-Sheet 2 Sept. 25,1956 T. SUTHERST 2,764,068

FAPER-MAKING MACHINES Filed NOV. 24. 1954 3 Sheets-Sheet 3 w v 7Attorney United States Patent PAlPER-MAKING MACHINES Tom Sutherst,Sheffield, England, assignor to Beloit Iron Works, lieioit, Wis, acorporation of Wisconsin Application November 24, 1954, Serial No.471,019

Claims. (Cl. 92--49) This invention relates to paper-making machines,its object being to facilitate the starting of the paper web in its runthrough the press section and dryer section of a machine using automaticvacuum transfer to transfer the web of paper from the wire into thepress section.

In the usual method of starting the run by jet-cutting a narrow tail atthe forming end of the machine, the disposal of the remaining major webofiers considerable diificulty because of the large accumulation ofbroke that results at the press section while the tail is beingforwarded through the machine. Removed at the press, or at one of thepresses, the broke has to be pulled to the front side of the machine byhand or by a broke conveyor, and the subsequent removal from the aisleof a large amount of broke calls for further handling.

According to the present invention, a paper-making machine press-sectionhas a bottom felt for its press (or for one of the presses) guideddownwardly after it has passed through the press, and is spaced from thesubsequent bottom felt serving to lead the web to the remainder of themachine, and a top press roll is provided on the exit side of the pressnip with a doctor movable into engagement with its surface beyond thepoint at which the web leaves the surface of the roll, the doctorextending across a width less than the total width of the press roll toleave an undoctored width corresponding to the width of the desiredtail, and the space between the bottom felts providing for the downwarddischarge of the doctored width. The doctor is moved into position whenrequired, being held clear of the roll during normal operation of themachine, when the normal doctor and collecting tray extending across thewhole face of the top press roll keep the roll surface clear of fibre,fluff, and the like.

The bottom felt of the press may extend beyond the press below the pathnormally followed by the web to the subsequent bottom felt, and a rollthen guides it downwardly, this roll being sufficiently spaced from theguide roll of the subsequent bottom felt for the broke doctored from thetop press roll to pass freely through the space.

The web reaches the press with a longitudinal cut to form the tail, andthe doctor removes the remainder of the web as broke for downwarddischarge, preferably to a hog-pit below the machine level, where it maybe beaten up with water and returned for re-use as stock.

Preferably, a creping doctor is used, to compact the broke to greaterbulk and to bring it to a more suitable condition for beating intostock. Advantageously, an airjet (e. g., a perforated pipe) extendsparallel to the doctor to assist in directing the broke towards thefelt.

Until the broke is being satisfactorily removed from the vicinity of thepress, the corresponding length of tail may be collected as waste in thetray behind the normal doctor above the press. Severing the wasteenables the tail to be handled forward, to a subsequent press or to thedryer section.

Where the bottom felt extends beyond the press to a guide roll beforebeing directed downwardly, a guard may be mounted above the pathnormally followed by the web on leaving the press, to counteract anytendency for the broke to be blown away from or beyond the feltextension. The guard leaves a gap between itself and the top press rollfor the doctored broke to fall towards the felt (assisted by the airjet) and at its other end may have a downward curve more or lessconcentric with the roll that guides the felt downwardly. Alternatively,the guard itself may receive the broke from the doctor, the air jetbeing positioned beyond and above the far end of the guard to direct thebroke downwards where the felt is guided downwards by the guide roll.In. this case, a deflector guard may be disposed between the doctor andthe air jet, more or less parallel to the main guard.

The broke doctor is preferably mounted so as to be quickly moved intoand out of contact with the press roll, e. g. by having a pivotalmounting, with an air cylinder to effect rocking. When a break occurs inthe machine, and broke removed by the full-width doctor begins tocollect in the trough above the press, the air cylinder may be quicklyoperated for the part-width doctor to bring the broke down for dischargeto the hog-pit; and the doctor may be quickly removed when the tail hasagain been passed through the machine thus allowing the gradual feedingof the full width of the web through the machine by means of the tail.

A guide may be provided to ensure that the broke does not adhere to thedownward run of the bottom felt, but is thrown clear into the hog-pit.

By way of example, several forms of installation according to theinvention will now be described in greater detail with reference to theaccompanying drawings, in which:

Figure l is a diagrammatic side elevation of the press section of apaper-making machine provided with one form of installation;

Figure 2 is a perspective view of a part of Figure 1;

Figure 3 is a diagrammatic side elevation, showing a modification of theinstallation shown in Figure 1;

Figure 4 is a diagrammatic side elevation of another type of presssection provided with a further form of installation; and

Figure 5 is a diagrammatic side elevation of a modification of Figure 4.

in Figure 1, a forming wire 1 is trained around a suction couch roll 2and a return roll 3, the paper web 4 being taken from the wire betweenthe couch roll and the re turn roll by a suction transfer roll 5 and anendless pickup felt 6 passing between the transfer roll and the formingwire. The endless felt 6 leads from the: transfer roll 5 to a firstpress consisting of a suction roll 7 and a top press roll 8, the felt 6returning to the transfer roll 5 around felt-, guide-, and stretch-rolls9. An endless bottom felt 10 serves both the first press and a secondpress comprising a suction roll 11 and a top press roll 12, the feltextending beyond the second press to a felt-roll 13 and returning to thefirst press around feltand guiderolls 14, 14A, and stretch-roll 15,being directed downwardly from the roll 13 to the roll 15.

For normal continuous running of the machine, the web 4 passes from thesecond press to a further section of the machine such as a third pressas shown in Figure 1, comprising bottom roll 16 and a top press roll 17,served by an endless bottom felt 18 which approaches the third pressafter turning around felt roll 19, the web 4 bridging the space betweenthe felt roll 13 and the felt roll 19. This space is made Wide enoughfor the mass of broke to pass, such space normally being made narrow, infact only of a width to ensure that an operative cannot trap his handsbetween the rolls.

In forming a tail for starting-up, a water jet 20, fixed at a point justprior to the point of contact of the forming wire 1 with the suctioncouch roll 2, cuts the web along a line 21 (Figure 2). Temporarycollection of the tail 22 thus formed takes place in a tray 23 behindthe normal full-width doctor 24 of the plain top roll of the secondpress. The broke 25 is removed from the top roll by a doctor 26extending across a width less than the total width of the top roll 12 bya width of the tail. An air jet 27 directs the broke 25 between a guard28 and the top roll 12 on to the bottom felt ill, to be carried over thefelt roll 13, and fall for collection into a hog-pit 29, lying below thespace between the felt rolls 13, 19.

The doctor 26 can quickly be brought into contact with the top roll 12,and as quickly be drawn out of contact with the top roll by aircylinders 3-3 and levers 31 (Figure 1) mounted on each end frame 32;carrying the top roll 12.

Alternatively, the guard 28 itself may receive the broke from the doctor26, as in Figure 3. An air jet 27A may then be positioned at the edge ofa deflector guard 33, beyond and above the far end of the main guard 23to direct the broke downwards into the space between the felt rolls 13,19.

In Figure 4, the transfer felt 6 leads from the transfer roll to aSimplex Press, passing through the bite between the suction roll 34 andthe first top plain press roll 35, and returning via the roll 35 andfelt-, guide, and stretch-rolls (not shown) to the transfer roll 5. Anendless bottom felt serves the bites of both the first top roll 35 andthe second top plain roll 36 with the suction roll 34 extending to afelt roll 13, and returning around feltand guide-rolls 14, 14A, andstretchroll to the bite of the first top roll. The felt roll 13 isspaced from the first felt roll 19 of a second bottom felt 18 leading toa second press (not shown).

The temporary collection of the tail 22 takes place in the tray 23behind the normal doctor 24 of the second top roll 36. The broke isremoved by a wide doctor 26 as described previously, which may beprovided with a deflector plate 37 in continuation of the doctor bladeto throw the broke 25 in its initial stage of formation into a brokeconveyor 38 above the extension of the bottom felt 10. A back plate 39and a hinged front plate 4!) limit the spread of the broke 25 across theconveyor. The conveyor 38 serves to lead the broke to the side of themachine. When the broke is to be directed to the hog-pit 29, the hingedfront plate 49 is swung upwards until vertical to prevent the brokepassing into the conveyor, and directs it down on to the extension. ofthe bottom felt 10, which carries the broke 25 over the felt roll 13. Aguide 41 directs the falling broke clear of the downward run of thebottom felt 10 into the hog-pit 29.

A broke conveyor such as 38 is advantageous on wide high-speed machines,such as newsprint machines, since it enables the broke to besatisfactorily disposed of until it proves convenient to carry it viathe bottom felt to the hog pit.

In Figure 5, the transfer felt 6 leads from the transfer roll 5 to aSimplex Press as in the installation shown in Figure 4, but the endlessbottom felt 10, which serves the bites of both the first top roll andthe second top roll 36 with the suction roll 34, is guided verticallydownwards directly from the suction roll 34, and returns around feltandguide-rolls 14, 14A, and stretch-roll i5 to the bite of the first toproll.

The temporary collection of the tail 22 takes place in the tray 23behind the normal doctor 24 of the second top roll 36. The broke 25 isremoved by a wide doctor 26 adapted to contact the surfiace of thesecond top roll 36 close to the second nip to allow the broke 25 to dropstraight into the hog-pit 2?. A deflector 42 may be provided inconjunction with the doctor 26 to guide the broke vertically downwardsThe doctor 26 (which may be a creping doctor) can quickly be broughtinto or out of contact with the top roll 36 by the cylinder and leverarrangement mentioned previously. A guide such as the guide 41 of Figure4 may be used if required.

What I claim is:

1. A paper-making machine press-section having a bottom press roll, atop press roll, a bottom felt passing through the nip of the rolls,guide means to lead that felt downwardly after its passage through thenip, a subsequent bottom felt spaced from the first bottom felt to leadthe paper web to the remainder of the machine, and a doctor movable intoengagement with the surface of the top press roll on the exit side ofthe nip beyond the point at which the paper leaves the surface of theroll, the doctor extending across a width less than the total width ofthe press roll to leave an undoctored width corresponding to the widthof the desired tail, and the space between the bottom felts providingfor the downward discharge of the doctored width.

2. A papenmaking machine press-section as in claim 1, wherein the doctoris a creping doctor, to compact the broke to greater bulk and to bringit to a more suitable condition for beating into stock.

3. A paper-making miachine press-section as in claim 2, comprising anair-jet extending parallel to the doctor to assist in directing thebroke downwardly.

4. A paper-making machine press-section having a bottom press roll, atop press roll, a bottom felt passing through the nip of the rolls, aguide roller beyond the press to lead that felt downwardly after itspassage through the nip, a subsequent bottom felt spaced from the firstbottom felt at the guide roller to lead the paper web to the remainderof the machine, and a doctor movable into engagement with the surface ofthe top press roll on the exit side of the nip beyond the point at whichthe paper leaves the surface of the roll, the doctor extending across awidth less than the total width of the press roll to leave an undoctoredwidth corresponding to the width of the desired tail, and the spacebetween the bottom felts providing for the downward discharge of thedoctored width deposited on the part of the first bottom felt extendingfrom the nip to the guide roller.

5. A paper-making machine press-section as in claim 4, comprising aguard mounted above the path normally followed by the web on leaving thepress, to counteract any tendency for the broke to be blown away from orbeyond the felt extension, with a gap between itself and the contactingpoint of the doctor with the roll and an air-jet which directs thedoctored broke through said gap.

6. A paper-making machine press-section as in claim 4, comprising aguard to receive the broke from the doctor, and an a"jet positionedbeyond and above the rear end of the guard to direct the broke downwardstowards the position where the felt is guided downwards by the guideroller.

7. A paper-making machine press-section as in claim 6, comprising adeflector disposed between the doctor and the air-jet, parallel to themain guard.

8. A paper-making machine press-section as in claim 4, comprising adeflector plate in continuation of the doctor, and a conveyor above theextension of the first bottom felt into which the doctor throws broke inthe initial stage of formation of broke.

9. A paper-making machine press-section having a bottom press roll, atop press roll, a bottom felt passing through the nip of the rolls,guide means to lead that felt downwardly direct from the bottom pressroll after its passage through the nip, a subsequent bottom felt spacedfrom the first bottom felt to lead the paper web to the remainder of themachine, and a doctor movable into engagement with the surface of thetop press roll on the exit side of the nip beyond the point at which thepaper leaves the surface of the roll, the doctor extending across awidth less than the total width of the press roll to leave an undoctoredwidth corresponding to the width of the desired tail, and the spacebetween the bottom felt providing for the downward discharge of thedoctored width.

10. A paper-making machine press-section having a bottom press roll, atop press roll, a bottom felt passing through the nip of the rolls,guide means to lead that felt downwardly after its passage through thenip, a subsequent bottom felt spaced from the first bottom felt to leadthe paper web to the remainder of the machine, a doctor movable intoengagement with the surface of the top press roll on the exit side ofthe nip beyond the point at which the paper leaves the surface of theroll, the doctor extending across a width less than the total width ofthe press roll to leave an undoctored width 6 corresponding to the widthof the desired tail, and the space between the bottom felts providingfor the downward discharge of the doctored width, and a guide to directbroke away from the downward run of the first bottom felt.

References Cited in the file of this patent UNITED STATES PATENTS1,338,094 Pope Apr. 27, 1920 1,687,847 Read Oct. 16, 1928 2,658,427 VerDoot Nov. 10, 1953 2,686,463 Hornbostel Aug. 17, 1954

